MATH221 Homework Exam Quizzes & Answers
(Complete Solutions 100% Correct)
A data set whose original x values ranged from 137 through 150 was used to generate a
regression equation of ŷ=-4.5x + 51. Use the regression equation to predict the value of
y when x=150. - ✔✔-624.0
An investment company wants to study how the changes in unemployment rate affect
one of its stock investments. Which statistical method would be best to use in this
situation? - ✔✔Regression analysis
If the coefficient of determination is 0.233, what percentage of the variation in the data
about the regression line is explained? - ✔✔23.3%
If the coefficient of determination is 0.738, what percentage of the variation in the data
about the regression line is unexplained? - ✔✔26.2%
If the independent variables explained more than 50% of the variation in the dependent
variables, which of the following would be true? - ✔✔The coefficient of
determination is above 0.5
The equation used to predict how tall a dog will be as an adult is ŷ=4.5 + 0.7x1 + 0.55x2,
where x1 is the height of the mother and x2 is the height of the father. Use this equation
to predict the height of a puppy whose mother is 42.8 inches tall and whose father is
47.1 inches tall. - ✔✔60.37 inches
The equation used to predict how long a cold will last is ŷ=-1.8 + 0.09x1 + 3.2x2 - 1.9x3,
where x1is person's temperature on the first day, x2 is number of people seen each day,
and x3 is the amount of sleep the person gets. Use this equation to predict how long a
(Complete Solutions 100% Correct)
A data set whose original x values ranged from 137 through 150 was used to generate a
regression equation of ŷ=-4.5x + 51. Use the regression equation to predict the value of
y when x=150. - ✔✔-624.0
An investment company wants to study how the changes in unemployment rate affect
one of its stock investments. Which statistical method would be best to use in this
situation? - ✔✔Regression analysis
If the coefficient of determination is 0.233, what percentage of the variation in the data
about the regression line is explained? - ✔✔23.3%
If the coefficient of determination is 0.738, what percentage of the variation in the data
about the regression line is unexplained? - ✔✔26.2%
If the independent variables explained more than 50% of the variation in the dependent
variables, which of the following would be true? - ✔✔The coefficient of
determination is above 0.5
The equation used to predict how tall a dog will be as an adult is ŷ=4.5 + 0.7x1 + 0.55x2,
where x1 is the height of the mother and x2 is the height of the father. Use this equation
to predict the height of a puppy whose mother is 42.8 inches tall and whose father is
47.1 inches tall. - ✔✔60.37 inches
The equation used to predict how long a cold will last is ŷ=-1.8 + 0.09x1 + 3.2x2 - 1.9x3,
where x1is person's temperature on the first day, x2 is number of people seen each day,
and x3 is the amount of sleep the person gets. Use this equation to predict how long a
